Chair.



E. W. HEDBERGU CHAIR.

APPLIUATION FILED JUNE a1, w12.

1 1 7,379., .,V Patented Nov.17,1914.

" "287 {Mwwn Fien l.

EDWARD W. HEDBERG, OF CHICAGO, ILLINOS.

To all 'whom it may concern.'

Be. it known that I, EDWARD W. HEDBERG, a citizen oi. the United States, residing at Chicago? in the county oit Coelir and State of Illinois, have invented certain new and usejful lmprovements in Chairs, of which the following is a specification.

This invention relates to chairs, to be used by harbors, dentists, and others, and which are equipped with mechanism by mains of wl ich the chair seat may be freely rotated and the height of the seat may be varied at the will of the operator.

The object of the invention is to provide mains for raising and lowering the chair that are of such .a nature that they may he controlled by the operator in a very simple and eiliecti ve way, a single movement o the foot ol the operator being suflicient to raise and lower the chair, and a second, or releasing, movement of the foot while the chair is rising being all that is necessary te bring the chair to rest at the hei ght desired.

ln the accompanying drawings, Figure l is a side elevation of a chair equipped with a certain 'Form of mechanism embodyingl the 'features ol. my invention. Fig. is a section of the chair support along the line Q-2 of Fig. 3 is a vertical Section of the telescopinp; tubes of the chair and its support showing` portions of the operating mecha nism. Fig. -l is a section along the line 4 4. o'l' Fig. f5. Fig'. 5 is a detail view showing 'the method ot' lockingf a portion of the velevaluingr apparatus in operative position.

The means which l have provided herein for raisin;Y and lowering the chair include operatin devices' which may be actuated by thcioot of the operator. The motive power which l have provided is an electric motor. By pressingl upon a button, positioned in the base o'll the chair. the motor ma y be operated and the chair raised. If the button is held in its operative position the chair will conti nue to rise until a maximum height is reached and it will then sink until a minimum height is r aiched. When, however, the chair rises to any desired height, it will come to rest at this height and remain s0 if the operator removes his foot. So that to move the chair from one position to another, it is lnecessary only for the operator to press the hutten until the chair fases to the desired height and then release the button.

The chair l is supported in this instanceu upon the base 2 by means of the frame 3 Specification cf Letters Patent.

Application filed June 21, 1912.

mounted on the base and inelositu;- a tubular upright l. in which is slidably mounted a piston-like tube or post 5 attached to the chair seat (i. ly this means the chair `lree to be rotated or to be moved vertically relative to the support the tube fl turning' on its base support, and the post 5 beingr inevable vertically in the tube. Concentric with the tube Ll and post 5 is a screw sha l't 7. This sha -t't is rotated by an electric motor l. the shaft oi which may be a continuation oi the shailt 7, or may he operatively connecteifl thereto. The shaft 7 is supported in a i`r^iction bearinpr f) in the lower end of the tube t and a guide bearing 0 connected with` the post 5. Projecting),l downwardly from the lower end of the post 5 are two hracltets. l0, at the lower ends oi each of which lis pivotcd a bent lever l1. The lowcrcnds ol these levers `form a threaded split-uut lit which is adapted to be closed to coact with the thread on the shaft 7. lllhen the upper ends of these levers are pressed upwardly the two members lil ol. the nut are forced into operative relation with the shaft, but when the upper arms are moved downwardly the nut members are released 'from the shalt. lily means ot this mechanism it will he seen that when the men'ihcrs oi the split-nut are held in coaction with the shaft 7 and the shaft is rotated in the proper direction the chair will be raised niiwardly.

Any suitable means may be provided to hold the. members o'l the nut in operative relation with the` shaft. The means which l' have provided herein comprise pins 14- with conieal ends which are adapted to project into depressions 1f in the levers 11. These pins are slidablv mounted in the brackets l0, and are backed by springs lo, the conipr'essioi'i ot which may he adjusted by means of the screws i7. lVhen these pins are forced hy the springs into the depressions 15 the splitnut will be locked in operative relation to the screw shaft.

The motor may be connected up to be, op erated by any suitable means. Herein .l have provided the buttons 18, placed in convenient positions in the hase "l, to each ot which the motor is operatively connected. The motor isadapted to rotate in one diree tion only, and the direction olf rotation is such asto cause the chair to move upward. Suitable means may he provided for limit ing; the height to which the chair will rise and for releasing the nut members 13 from the.

" @heir-continue. to

` are lower ends or screw shaft so to allow 'the chair to sink. llhe ineens vhieh have provided comprise the stops which are slidebly but non-rotata-blyr morente the hollow I,guides 2O lined. to the tube d. Normally these stops held in the guides by the posi; 5, but when the post rises so es to 'clear the end oi the stops, the 2i will force the stops inwardly. L. ns 22 fixed te rods 23 ettached to t. tops 19, end prevent the stops from beine. too nier inwardly. As the e `the upper ends of the .gevers ll will. e' e in Contact with the pron jecting stops: and pins le will be forced ont ot the de fassions i5, the nut members will be "reed out of Contact with the shaft T, ane o cheir will then he released and will be to sink. rthe pins' lli will into depressions 15a end the levers ioeifced in, inoperative posiends of the stops i9 are f on. y upper sine, ene. the iowor end the post o is beveled, so that the stops will forced ouf,4 by the poet when the latter ends, to prevent the stops holding the elevated.

e post nts snugly in the tube d so there is orale, iii'eny, leakage ofeir J` l. riced a `oet oook 2d, vent to which gnsted. by means 'the shanlr "etvreen the Mills; and .the tube 4t is air Y A. oe

i @its maximum height, the air between the lin he bottom of the tube gils i f 7 l.

W nen .ne ehalr-is released 'upon rea/cnnot @is cushion, preventing' sinking; of the is held closed by the pressure of the contained nir the chair sinks. A oolleiv' .limits the downward motion of 'the @heir by coming in, eo. .et with the upperfend of the tubel. As Lne collar 27 comes in Contact with the tube. the opper ends of the levers 1l come in Contact with the pins 9,8 fixed inthe wallet the tube l, and the nut members 13 reed together into operative relation the locking pins ifibeing et with the shaft, the sume time .forcee from the depressions ifi* and into the depressions l5, and thus signin looking the s plitnu't in operative oon'- practice operation is as follows: The mierator places his foot upon a hutten, e, nnztor is thus started, the shaft rod, und the chair raised. lfhis will ,oo

om" in whatever position the (their may fbe,

at 'when the button o., sis the s'ilit-nut will then ,perative nosiiion. The chair ou bie ri isod ,land it will continue to 'o ovi di nig it itch is 'i rise until e inagximuni l'seilrght is reaohed. lit

the.r be lutomatically released `and it sink until the minimum l'leight 1s Lili he tnbese'.- and the post 5 will reached. If, however, the operator releases the button, the Chair will immediately come to rest, if it is rising at the time. if it is sinking; at the time the button is released, it will continue to sink to the minimum position, and will then come to rest. fdo that it it is desired to bring,` the chair to rest at the minimum position, the operator removes his footas the eheir is sinking. if it is desired to bring the chair to rest above this position he removes his foot, as the chair is rising, when .it reaches the desired height. flrlthoughl have described somewhatA in detail' the .mechanism provided, it is to be understood that modilieations may be made 'therein by those skilled in the'art without departing); from the spirit oi' this invention. claim as my invention: l.' lin e chair, the combination of a seat; means to elevate the seat; means to limit the height to which said seat may be elevated, said elevating means comprising;l a Vertical screw connected with the base of said chair; means for rotating said screw; a nut composed of two members, said nut being connected with said seat and adapted to coaot with said screw, said limitingl means cornprising an arm on each member of said nut; stops connected with the support of said seat; and means for moving; said stops into th path of motion oi', seid arms, whereby members are moved out of Contact wit seid screw.

w (their, e @heir seat and means for raising; said sent Comprising a screw shaft and e clutch normally conci-ine; with said shaft, ineens for rotating thel'shatt, means for rei/easing the elutoh when a' predeter A,mined height has been reached, means for 'locking seid clutch in its inoperative 'posh tion, whereby said chair is left unsupported, means for moving; said clutch into operative position when said chair has sunk to 'a predetermined point,y and means including a portion o said lockingfmeans for looking seid clutch in operativeposition.

3. in e chair, choir seat, `nie-ens for snpporting and reismgsaid sost, Ineens for controlling said raising l`Ineans automatic means for rendering; inoperative said supporting' and raisingvmeans, yielding means resisting the downward motion of said chair,

v andautomatic. means vfor placing' said supporting and said raising Ineens in operating position.' V d. A chair comprising a seat and esuppori'. therefor, a 'vertical Cylinder, `e piston in seid cylinder, one of the two lest elements being stationarily mounted insaid Support andthe other being carried by said seat and `verticnlly movable therewith, means for raising; the seat including; e rotary 4screw shaft mounteo in the support, a nut ydevice mounted to travel with the Sent and ar- Jranged to be moved into and out oi' threaded asuppor, therefor, a rotatable-cylinder verm tcally mounted in said supporg., .no piston carried by said seat and projecting down- Wardly into said cylinder, an electric motor dxeotly beneath said cylinder and having ifbs shaft disposed vertically, a, screw shaft f eoazfal with the motor shaft and rigidly connected thereto, said screw shaft entending upvverdly through smid cylncler and a lo nul; device movably carried by said piston and emngecl no lje automatically moved lnto and out of engagement vvlla said screw snail; be llmlts of travel of mld plston.

ln tes.1mony whereof my slgnatme 1n the 'picesence of two Wltnesses.

EDWARD TW.. HEDBERG.

lftnesses EARL C. CARLSGN, @nom-ln L, CHINDAHL. 

